Method, system and gateway device for enabling interworking between IP and CS networks
Patent Information
- Authority / Receiving Office
- US · United States
- Current Assignee / Owner
- Publication Date
- 2011-03-01
- Estimated Expiration
- Not applicable · inactive patent
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Abstract
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of U.S. Provisional Application Ser. No. 60 / 456,953 entitled, “Method, System and Gateway Device for Enabling Interworking Between IP and CS Networks,” filed Mar. 25, 2003, the entire contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method, system and gateway device for enabling interworking between an Internet Protocol (IP) network, such as an IP Multimedia Subsystem (IMS) network, and a circuit-switched (CS) network, such as a Global System for Mobile Communication (GSM) network.
[0004] 2. Description of the Related Art
[0005] In order to achieve access independence and to maintain a smooth interoperation with wired terminals across the Internet, an IP multimedia subsystem (IMS) core network as specified e.g. in the 3GPP (Third Generation Partnership Project) specification TS 23.228 has been developed to ...
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Embodiment Construction
[0032]The preferred embodiment will now be described on the basis of a SIP conferencing functionality in an IMS network environment.
[0033]FIG. 1 shows a schematic block diagram of the network architecture according to the preferred embodiment, wherein a GSM (Global System for Mobile communication) network 10 is connected to a SIP-based IMS network 30 via a Media Gateway Control Function (MGCF) 20 which controls a Media Gateway function (MGW) 40. The MGCF 20 is arranged to control the parts of a call state which pertain to connection control for media channels in the MGW 40. It communicates with Call Session Control Functions (CSCFs) as defined in the 3GPP specification TS 23.228. Furthermore, the MGCF 20 selects a CSCF depending on the routing number for incoming calls from legacy networks, such as the GSM network 10. The gateway functionality is achieved at the MGCF 20 by performing protocol conversion between ISUP and the IMS call control protocols. Out-of-band information assumed...